A would-be around-the-world balloonist is preparing to make a trip in a helium-filled balloon. The trip begins in early morning at a temperature of 15oC. By mid-afternoon, the temp has increased to 30oC. Presuming the pressure remains constant at 1.0atm, for each mole of helium, calculate
a. The initial and final volumes
b. The change in internal energy
c. The heat transferred
d. ΔH for the process
e. Elucidate the relationship between the answers to (c) and(d)